I got a message from beckblazer, but my email is down now, so I'll post it here. Nothing too bad.

Most GM dealers will be able to tell you if your TB has had any recall work done to it or not. Becuase it's a recall, they track it on a VIN by VIN basis. So if the previous owner (or dealership that bought/resold) got the work done, it will be on file with GM tied into your VIN number.